Embodiments of the disclosure generally relate to methods of removing a ceramic coating from a substrate. More particularly, embodiments of the disclosure relate to methods of removing a ceramic coating used as a mask for selective nitrogenation of a metallic component.
A number of advanced ceramic coating systems are often applied to one or more surfaces of metallic components. The ceramic coatings are often used to protect the surface or substrate, e.g., by providing electrical or thermal insulation, or by providing wear resistance, corrosion resistance, or oxidation resistance. A wide variety of specialty materials are available for these uses. In some instances, the various ceramic coatings mentioned above may be used for purposes other than surface protection. For example, they may be used as gas-barrier coatings; or for masking sections of a substrate while other processing steps are carried out on the substrate.
Many of these ceramic coating materials are designed to be permanently deposited on the substrate, and not to be removed during the life of the component on which these coatings are deposited. However, some of the performance coatings described above may be useful for applications in which the coatings need to be removed at some point. One example relates to various ceramic coatings used as masking materials, e.g., during selective nitrogenation of metallic components to vary the magnetic properties.
However, conventional materials and processes for removing various ceramic coatings from substrates may exhibit drawbacks. Some of the coating removal methods are unable to remove most of the coating material from the surface. Other coating removal methods may be somewhat effective in removing the coating material, but damage or otherwise modify the underlying substrate, e.g., damage the underlying metallic substrate used during nitrogenation. Thus, there is a need for improved methods of removing ceramic coatings from a substrate.